intel_sst: Save audio state across D3 on Medfield

During suspend and runtime_suspend audio dsp will be in D3 state
and will loose its context.

This patch adds support in driver to save the dsp context
and restore this context during resume

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Ramesh Babu K V <ramesh.babu@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 63 insertions, 4 deletions

diff --git a/drivers/staging/intel_sst/intel_sst.c b/drivers/staging/intel_sst/intel_sst.c
index 81c24d1..2f21f42 100644
--- a/drivers/staging/intel_sst/intel_sst.c
+++ b/drivers/staging/intel_sst/intel_sst.c
@@ -316,9 +316,25 @@ static int __devinit intel_sst_probe(struct pci_dev *pci,
 	if (sst_drv_ctx->pci_id == SST_MRST_PCI_ID) {
 		ret = misc_register(&lpe_dev);
 		if (ret) {
- 			pr_err("couldn't register misc driver\n");
+			pr_err("couldn't register LPE device\n");
 			goto do_free_misc;
  		}
+	} else if (sst_drv_ctx->pci_id == SST_MFLD_PCI_ID) {
+		u32 csr;
+
+		/*allocate mem for fw context save during suspend*/
+		sst_drv_ctx->fw_cntx = kzalloc(FW_CONTEXT_MEM, GFP_KERNEL);
+		if (!sst_drv_ctx->fw_cntx) {
+			ret = -ENOMEM;
+			goto do_free_misc;
+		}
+		/*setting zero as that is valid mem to restore*/
+		sst_drv_ctx->fw_cntx_size = 0;
+
+		/*set lpe start clock and ram size*/
+		csr = sst_shim_read(sst_drv_ctx->shim, SST_CSR);
+		csr |= 0x30060; /*remove the clock ratio after fw fix*/
+		sst_shim_write(sst_drv_ctx->shim, SST_CSR, csr);
 	}
 	sst_drv_ctx->lpe_stalled = 0;
 	pm_runtime_set_active(&pci->dev);
@@ -374,16 +390,17 @@ static void __devexit intel_sst_remove(struct pci_dev *pci)
 	sst_drv_ctx->sst_state = SST_UN_INIT;
 	mutex_unlock(&sst_drv_ctx->sst_lock);
 	misc_deregister(&lpe_ctrl);
-	if (sst_drv_ctx->pci_id == SST_MRST_PCI_ID)
-		misc_deregister(&lpe_dev);
 	free_irq(pci->irq, sst_drv_ctx);
 	iounmap(sst_drv_ctx->dram);
 	iounmap(sst_drv_ctx->iram);
 	iounmap(sst_drv_ctx->mailbox);
 	iounmap(sst_drv_ctx->shim);
 	sst_drv_ctx->pmic_state = SND_MAD_UN_INIT;
-	if (sst_drv_ctx->pci_id == SST_MRST_PCI_ID)
+	if (sst_drv_ctx->pci_id == SST_MRST_PCI_ID) {
+		misc_deregister(&lpe_dev);
 		kfree(sst_drv_ctx->mmap_mem);
+	} else
+		kfree(sst_drv_ctx->fw_cntx);
 	flush_scheduled_work();
 	destroy_workqueue(sst_drv_ctx->process_reply_wq);
 	destroy_workqueue(sst_drv_ctx->process_msg_wq);
@@ -398,6 +415,46 @@ static void __devexit intel_sst_remove(struct pci_dev *pci)
 	pci_set_drvdata(pci, NULL);
 }
 
+void sst_save_dsp_context(void)
+{
+	struct snd_sst_ctxt_params fw_context;
+	unsigned int pvt_id, i;
+	struct ipc_post *msg = NULL;
+
+	/*check cpu type*/
+	if (sst_drv_ctx->pci_id != SST_MFLD_PCI_ID)
+		return;
+		/*not supported for rest*/
+	if (sst_drv_ctx->sst_state != SST_FW_RUNNING) {
+		pr_debug("fw not running no context save ...\n");
+		return;
+	}
+
+	/*send msg to fw*/
+	if (sst_create_large_msg(&msg))
+		return;
+	pvt_id = sst_assign_pvt_id(sst_drv_ctx);
+	i = sst_get_block_stream(sst_drv_ctx);
+	sst_drv_ctx->alloc_block[i].sst_id = pvt_id;
+	sst_fill_header(&msg->header, IPC_IA_GET_FW_CTXT, 1, pvt_id);
+	msg->header.part.data = sizeof(fw_context) + sizeof(u32);
+	fw_context.address = virt_to_phys((void *)sst_drv_ctx->fw_cntx);
+	fw_context.size = FW_CONTEXT_MEM;
+	memcpy(msg->mailbox_data, &msg->header, sizeof(u32));
+	memcpy(msg->mailbox_data + sizeof(u32),
+				&fw_context, sizeof(fw_context));
+	spin_lock(&sst_drv_ctx->list_spin_lock);
+	list_add_tail(&msg->node, &sst_drv_ctx->ipc_dispatch_list);
+	spin_unlock(&sst_drv_ctx->list_spin_lock);
+	sst_post_message(&sst_drv_ctx->ipc_post_msg_wq);
+	/*wait for reply*/
+	if (sst_wait_timeout(sst_drv_ctx, &sst_drv_ctx->alloc_block[i]))
+		pr_debug("err fw context save timeout  ...\n");
+	sst_drv_ctx->alloc_block[i].sst_id = BLOCK_UNINIT;
+	pr_debug("fw context saved  ...\n");
+	return;
+}
+
 /* Power Management */
 /*
 * intel_sst_suspend - PCI suspend function
@@ -417,6 +474,8 @@ int intel_sst_suspend(struct pci_dev *pci, pm_message_t state)
 		pr_err("active streams,not able to suspend\n");
 		return -EBUSY;
 	}
+	/*save fw context*/
+	sst_save_dsp_context();
 	/*Assert RESET on LPE Processor*/
 	csr.full = sst_shim_read(sst_drv_ctx->shim, SST_CSR);
 	csr.full = csr.full | 0x2;